Air cleaning devices and components therefor



E. M. BERLY 2,945,554

AIR CLEANING DEVICES AND COMPONENTS THEREFOR July 19, 1960 2Sheets-Sheet 1 Filed Jan. 11, 1957 INVENTOR wmrd 7%Zarly M 9 A'ZTY' 7 E.M. BERLY July 19, 1960 AIR CLEANING DEVICES AND COMPONENTS THEREFORFiled Jan. 11, 1957 2 Sheets-Sheet 2 INVENTOR (Edward 2%ZZZ- ATTY UnitedStates Patent '0 AIR CLEANING DEVICES AND COMPONENTS THEREFOR Edward M.Berly, 149 Christina Ave., Newton Highlands, Mass.

Filed Jan. 11, 1957, Ser. NO. 633,774

10 Glaims. (Cl. 183-37) The present invention relates to aircleaningdevices and, more jparticularly, to devices for removing fromthe air undesired particles and contaminants such as soot, pollen andotherdusts and/or ozone, fumes and other vapors.

Objects of the present invention are: to provide, for

effectively collecting particles of all sizes found in ordi- .nary air,anair cleaning device simply constructed from a filter of large area andlong life and a fan of low .power consumption that cooperate in anovelrnanner, the filter coupling eflicient dust collection witha lowpresvdisposablecomponentsare readily accessible; and to dis- ..pose thecomponents of a device of the foregoing type at advantageouspositionsrelative tO-each-other as well asrelative tothe floor of a room inwhich-the device is located.

Other objects of the-present'invention will inipart be obvious and willin'part appear hereinafter.

The invention accordingly comprises the devices and components thereofpossessing the features, properties and relation of elements that-ar'eexernplified in.the following detailed disclosure, and-thescope ofwhich will be indicated in the appended claims.

For a fuller understanding of the nature-andobjects of the presentinvention, referenceshould'be had to-the following detailed descriptiontaken in, con'ection with the accompanying drawing wherein:

Figure l is a cross sectional view ofapreferredembodiment of the presentinvention the cross section being taken along the line 1-1 ofFi gure 3to be described below;

Figure 2 is a fragmentary crosssectional viewrof the preferredembodiment, taken -along the dine 2- -2- of Figure .j Figure 3 is across sectional view o f the preferred-embodiment, taken along the line3-3 of- Figure '1;

Figure 4 is a fragmentary perspective view of a component of thepreferred embodiment;

Figure 5 is a cross-sectional view'of janother component of thepreferred embodiment, taken along-the line '5-5 ofFigure 3; I

Figure 6 is abroken away cross sectional view ofzthe the preferredembodiment, taken along the line 6 6 ofFig'ure'l; i i V Figure 7 is "aschematic diagram of the electrical circuitof the preferredembodiment;and Y j Figure-'8 is-a broken away-perspective view-of the pre-'rferredsembodim'ent *YWith'freference first-toFig'ures land 8generally, the

I,illustratedidevice comprises a=housing 20-"through which from itssupporting ribs 48.

air is drawn by a motor driven fan 22. Within the housing are a bank 24of filter bags that remove dust from the air, a germicidal lamp 26 thatacts upon air from the filter bags, and a porous matrix 28 that abfsorbs and/or adsorbs vapors from air passing therethrough andtherearound.

Housing 29 has substantially vertical side walls 32, a substantiallyhorizontal bottom wall 34 and an open 'top' covered by a removable lid36. Lid 36 has a substantially horizontal top wall 38 and substantiallyvertical sidewalls 40, the lower edges of which normally are held inregister with the upper edges of side walls 32' by frictional engagementwith corner stays 42 that are secured at each of the four corners ofhousing 20 and project upwardly therefrom. The edges of side walls 40are medially cut away to provide ports 44 through which air may enterhousing 20. Bottom wall 34 is cut away at its four corners to providelarge ports 46. Housing 10 is supported. above the floor by four legs47. Ports 46, through which air leaves the housing at a low velocity,and legs 47 which separate ports 46 from the floor by aconsiderabledistance, preferably 8 to 18 inches, prevent the stirring upof dust from the floor. 7

The four filter bags that constitute bank 24 are supported as follows.Affixed to walls SZadjacent to their upperedges are foursupportingribs48. Removably resting Onthese ribs is a plate Silhaving outer edges 52that snuglyfollow the inner edges of walls 32 and 'stays 42.-Plate,50-is-provided with four openings 54 out its periphery sothatresil-ient' band 59 exerts pressure throughout the mouth .of bag24..A rail 57 extends up: wardly from plate 50 throughout its peripherytoprevent any view of the interior of housing 32through ports 44 and toenable manual grippingfor. removal of plate 50 Affixed to sidewalls 32on bottom. wall 34 are four supporting ribs 60.. Secured to the upperedges of supporting ribs .60 is a centrally apertured panel 62, theouter edgesof which snugly follow side walls 32. The blades of fan 22are positioned within. the aperture so that vertically they extend bothabove and below panel,62.

Germicidal lamp 26 and porousmatrix 28 arecarried by four upstandingposts 64, 66, 68 and 70, which are secured to the upper face ofpanel 62.The edges of porous matrix 28 rests on .these posts and are retainedthereon by clips 72 and 74 which are affixed by screws to posts 64 and66. Sockets 76 and.7$, for the opposite terminals of lamp 26 are carriedby brackets 82 and 84 that are aflixedtoposts 68 and 70. The innerfaces. 86 of side walls 32 are providedwith .reflective aluminized paperto maximize theefiect of germicidal lamp 26.

. Asindicated above, filter bags 24, .porous matrix 28 and fan 22 aredesigned to cooperate in a particular manner which will now be describedspecifically. v Filter b ags,24 are composed of ,highly dispersednonwoven fibres, ,f 0r examplev of regenerated .cellulose that rangefrom 0.5 to 15 microns in diameter. Preferably, fan, 22 produces a facevelocity of air throughthe bag of from 1 to 40 ft/min. (cubic feet ofair per square foot of bag face per minute), the best'velocit'ylbeinggenerally excellent pressure drop being .002 p.-'s.i-. Because the bagshang-freely, they may be supported only .attheirimouths notwithstandingtheir. large area,

Porous matrix 28 (Figure 5 includes a layer of activated carbon granules38 (of large surface area) carried by a support that minimizes attritionof the carbon resulting from shock due to motion of the air with respectto it, and that keeps the granules dispersed in order to provide minimumair resistance. This support includes a pair of fibre mats 90 and 92between which the carbon granules are sandwiched in a quantity rangingpreferably between 2 and 8 oz./sq. ft. In alternative embodiments carbongranules 88 are replaced by other inorganic granules composed, forexample, of an aluminum compound such as alumina or a silicon compoundsuch as silica. Preferably these granules are characteriezd by aratingwithin the range 4 to 200 mesh (Tyler, A.S.T.M.). Thesefibre matsare composed of any suitable natural or synthetic strands, e.g. strandsof straw or glass, woven into springy, ope'n structures. A pair ofmetallic webs 94 and 96, the edges of which are clamped together by achannel shaped frame 98, compress -mats 90 and 92 sufliciently to keepthe carbon dispersed and immobile. Porous matrix 28 is positioned onposts 64, 66, 68 and 70 so that air from filter bags 24 passes around aswell as through it. Nevertheless, recycling of air through the apparatusunit is sufficient to reduce the undesired vapor concentrationeffectively. In an alternative embodiment the arrangement is such thatall air passing through the apparatus must pass through the porousmatrix.

It has been found from experience that most of the noise generated froma fan is air noise and, that for quiet operation, the rmistance to airfiow must be minimized. This consideration dictates the selection of afan that has very low power requirements. A fan of maximum efiiciencywhen delivering the required power in operating on a filtering systemwith minimum resistance provides the quietest operation possible. It hasbeen found from experimental data that for quiet operation (belowconversational level) the brake horsepower should not exceed 4X10"H.P./ft./min. for waking hours or 1.5 X 10- H.P./ft./min. for sleepinghours. The present embodiment has been designed so that at high speedthe fan delivers 0.007 HP. at 250 ft./min. and at low speed .0025 HP. at175 ft./min.

A schematic diagram of the electrical control circuitry for fan 22 andlamp 26 is shown in Figure 7. Mechanical details of the circuit diagramare shown in Figures 1 and 6. As shown, alternating curent from a source96 is applied through leads 98 and 100 across a lamp channel 102 and amotor channel 104. Channel 102 includes lamp 26 having a parallelstarter 106 and a series ballast 108. Channel 104 includes the motor forfan 22 in series with a resistor 110 shunted by a switch 112 for varyingthe motor speed. A line switch 114 controls the operation of the entireunit.

In operation, matrix 28 and lamp 26 are readily replaceable when lid 36and plate 50 are removed. When lid 36 is removed, bags 24 are readilyreplaceable by similar bags, the free edges of which are folded overrims 58 and secured thereto by resilient bands 59. The entire deviceoperates when switch 114 is closed, i.e., fan 22 draws air through bags24, past lamp 26 and through and around matrix 28. The speed of fan 22is controlled by switch 112. The device recycles the air in a large roomwith suificient rapidity to cleanse it efficaciously in a short time andthereafter to maintain a low level of undesired dust, vapor andbacteria.

Since certain changes may be made in the above product without departingfrom the scope of the invention herein involved, it is intended that allmatter contained in the above description or shown in the accompanyingdrawing shall be interpreted in an illustrative and not in a limitingsense.

What is claimed is:

1. An air cleaning device comprising a housing defining a compartmenthaving first ports and second ports, means between said first ports andsaid second ports providin a plurality of openings except for which saidmeans substantially seals the portion of said compartment providing saidfirst ports from the portion of said compartment providing said secondports, a plurality of filter bags composed of highly dispersed non-wovenfibers, the mouth portion of one each of said filter bags joining theportion of said means defining one each of said openings, the closedportion of said one each of said filter bags extending into said portionof said compartment defining said second ports, and a fan in saidportion of said compartment defining said second ports, a matrix ofdispersed granules of activated inorganic material positioned be tweensaid bags and said fan, said fan drawing air in sequence through saidfirst ports, said bags, said matrix and said second ports, said fibersranging from 0.5 to 15 microns in diameter, said fan being operative todraw air through said bags such that the face velocity of said airthrough said bags ranges from 1 to 40 cu. ft./sq. ft./min., theresistance to the flow of said air being such that the pressure dropacross the face of said bags is within the range of from .0007 to .007p.s.i.

2. The air cleaning device of claim 1 wherein said fibers are composedof regenerated cellulose.

3. An air cleaning device comprising a housing defining a compartmenthaving a first portion providing first ports and a second portionproviding second ports, a panel between said first portion and saidsecond portion, said panel providing openings except for which saidpanel substantially seals said first portion from said second portion, aplurality of filter bags composed of highly dispersed nonwoven fibersranging from 0.1 to 15 microns in diameter, the open portion of saidbags defining the mouths thereof being connected to portions of saidpanel defining said openings, the closed portion of said bags extendinginto the second portion of said compartment, a fan in said secondportion of said compartment, a matrix of dispersed granules of activatedinorganic material, positioned between said bags and said fan, said fandrawing air, in sequence, through said first ports, said bags, saidmatrix and said second ports, the face velocity of said air through saidbags being within the range of from 1 to 40 cu. ft./ sq. ft./min., theresistance to flow of said air being such that the pressure drop acrossthe face of said bags is Within the range of from .0007 to .007 p.s.i.

4. An air cleaning device comprising a housing defining a compartmenthaving a first portion defining first ports and a second portiondefining second ports, a panel between said first portion and saidsecond portion providing openings except for which said panelsubstantially seals said first portion from said second portion, aplurality of filter bags having mouth portions connected to portions ofsaid panel defining said openings and closed portions extending freelyinto said second portion of said compartment, a porous matrix mounted insaid housing with one face of said matrix adjacent to said closedportion of said bags, said matrix being composed of activated carbongranules, and a fan mounted in said housing adjacent to the other faceof said matrix remote from the closed portions of said bags, said fanserving to draw air in sequence through said first ports, said bags,said matrix and said second ports, said porous matrix including a pairof fibrous mats, dispersed granules of activated inorganic material,sandwiched between said fibrous mats, reticulated webs pressing saidfibrous mats toward each other, and a clamping rim engaging the edges ofsaid reticulated webs, said granules being characterized by a ratingwithin the range 4 to 200 mesh, said fibrous mats being composed ofwoven strands.

5. An air cleaning device comprising a housing defining a compartmenthaving a first portion defining first ports and second portion definingsecond ports, a panel between said first portion and said second portionproviding openings except for which said panel substantially seals saidfirst portion from said second portion, a plurality of filter bagshaving mouth portions connected to portions of said panel defining saidopenings and, closed portions extending freely into said second portionof said compartment, a porous matrix of activated inorganicmaterialmounted in said housing with one face of said matrix adjacent to saidclosed portions of said bags, a fan mountedin said housing adjacent tothe other face of said matrix remote from the closed portions of saidbags, saidfanserving to draw air in sequence through said first ports,said bags,rsaid matrix and said second ports, and a germicidal lamppositioned between said filter bags and said porous matrix.

6. An air cleaning device comprising a housing defining a compartmenthaving a first portion providing first ports and a second portionproviding second ports, a panel between said first portion and saidsecond portion, said panel providing openings except for which saidpanel substantially seals said first portion from said second portion, aplurality of filter bags composed of highly dispersed non-woven fibersranging from 0.1;to,,1-5 microns indiameter, the open portion of'saidbags defining the mouths thereof being connected ,to portions-of saidpanel defining said openings, the closed portion of said bags extendinginto the second portion of said compartment, a fan in said secondportion of said compartment, a matrix of dispersed inorganic materialpositioned between said bags and said fan, said fan drawing air, insequence, through said first ports, said bags, said matrix and saidsecond ports, the 'face velocity of said air through said bags beingwithin the range of from 1 to 40 cu. ft./sq. ft. /min., the resistanceto flow of said air being such that the pressure drop across the face ofsaid bags is within the range of from .0007 to .007 p.s.i., said fanoperating at substantially maximum efficiency when delivering therequired power.

7. The air cleaning device of claim 6 wherein each of said openings insaid panel is defined by a rim and the mouth portions of said bags areconnected to said rim by being wrapped thereon and joined thereto by anelastic band.

8. An air cleaning device comprising a housing defining a compartmenthaving a first portion providing first ports and a second portionproviding second ports, a panel between said first portion and saidsecond portion, said panel providing openings except for which saidpanel substantially seals said first portion from said second portion, aplurality of filter bags composed of highly dispersed non-woven fibersranging from 0.1 to 15 microns in diameter, the open portion of saidbags defining the mouths thereof being connected to portions of saidpanel defining said openings, the closed portion of said bags extendinginto the second portion of said compartment, a fan in said secondportion of said compartment, a matrix of inorganic material selectedfrom the class consisting of carbon, silicon and aluminum containing gasabsorptive materials, said matrix being disposed between said bags andsaid fan, said fan drawing air, in sequence, through said first ports,said bags, said matrix and said second ports, the face velocity of saidair through said bags being within the range of from 1 to 40 cu. ft./sq.ft./min. the resistance to flow of said air being such that the pressuredrop across the face of said bags is within the range of from .0007 to.007 p.s.i., said fib e-rs being composed of regenerated cellulose.

9. An air cleaning device comprising a housing and, therewithin, a motordrive fan for drawing air therethrough, a bank of filter bags forremoving dust from said air, a germicidal lamp for destroying bacteriain said air, and a porous matrix for absorbing and adsorbing vapors fromsaid air, said housing having substantially vertical side walls and asubstantially horizontal bottom wall, said housing providing an opentop, a removable lid covering said open top, said lid having asubstantially horizontal top wall and substantially vertical side walls,the lower edges of said side walls of said lid being registered with theupper edges of said side walls of said housing, said lower edges of saidlid being medially cut y t rrovidepon thr ug w h a r may'ent s housing,saidbnttomwall of said housing being cut away to, provideports throughwhich air may leave said housing, a .pluralityioflegs affixed to saidhousing for supporting. said housingaboveaffioor with said ports of saidbottom-wall-spaced from said floor a distance ranging fromS (0,18inches,.supporting ribs afiixed tosaid side walls of: saidhousingadjacent to said upper edges, a plate removablyrresting on said ribs,said plate having outer edges that snugly follow the inner edges of saidside walls of ..said,housing, said platebeing provided with apluralityof openings that account for a proportion greater thanone-third of theareaof said plate, upstanding-rims bounding said openings of said plate,supporting ribsadjacent tothe lower edges of said side walls of saidhousing,-a panel securedtothe upper edges of saidssupportingfribs, said:panel having a central aperture, :the outer edges of said panel snuglytollowingsaid side wallsof-said housing, said fan being so supportedwithinsaidhousing:thatitsblades are positioned within said centralaperture so that they extend both above and below said panel, aplurality of posts upstanding from said panel, the edges of said porousmatrix resting upon said posts, sockets carried by said posts, saidsockets receiving the terminals of said germicidal lamp, a reflectivealuminized layer covering a proportion of the inner surfaces of the sidewalls of said housing, said porous matrix including a pair of fibrousmats, dispersed granules of activated inorganic material sandwichedbetween said fibrous mats, reticulated webs pressing said fibrous matstoward each other, said edges of said porous matrix including a clampingrim engaging the edges of said reticulated webs, said granules beingcharacterized by a rating within the range 4 to 200 mesh, said fibrousmats being composed of woven strands, said filter bags be ng composed ofhighly dispersed non-woven fibers ranging from 0.1 to 15 microns indiameter, said fan being operative to draw air through said bags suchthat the face velocity of said air through said bags ranges from 1 to 40cu. ft./sq. ft./min., the resistance to the flow of said air being suchthat the pressure drop across the face of said bags is within the rangeof from .0007 to .007 psi.

10. An air cleaning device comprising ahous ing and, therewithin, amotor driven fan for drawing arr therethrough, a bank of filter bags forremoving dust from said air, a germicidal lamp for destroying bacteriain said air, and a porous matrix for absorbing and adsorbing vapors fromsaid air, said housing having snbstantially vertical side walls and asubstantially horizontal bottom wall, said housing providing an npen topand a removable lid covering said open top, said lid having a top wallthat is substantially horizontal and edges that are substantiallyregistered with the upper edges of said side walls of said housing,means at theupper portion of said housing providing ports through whichan may enter said housing, means at the lower portion of said housrngproviding ports through which air may leave said housing, a plurality oflegs affixed to said housing for supporting said housing above a floorwith said ports of said bottom wall spaced from said floor a distanceranging from 8 to 18 inches, a plate at said upper edges of saidhousing, said plate having outer edges that snugly follow the innerdeges of said side walls of said housing; said plate being provided witha plurality of openings that account for a proportion greater thanone-third of the area of said plate, boundary means at said openings ofsaid plate, said filter bags projecting downwardly through said openingsof said plate, said filter bags defining said open tops overlapping saidboundary means, fastening means for securing said filter bags to saidboundary means, said openings being such that said fastening means exertpressure completely around said edge portions of said bags,

a panel of said lower portion of said housing, said panel 7 having acentral aperture, the outer edges of said panel snugly following saidside walls of said housing, said fan being so supported within saidhousing that its blades are positioned within said central aperture sothatthey extend both above and below said panel, said porous matrix andsaid germicidal lamp being disposed between said bags and said panel, areflective aluminized layer covering a proportion of the inner surfacesof the side walls of said housing, said porous matrix including a pairof fibrous mats, dispersed granules of activated inorganic materialsandwiched between said fibrous mats, reticulated webs pressing saidfibrous mats toward each other, said edges of said porous matrixincluding a clamping rim engaging the edges of said reticulated webs,said granules being characterized by a rating within the range 4 to 200mesh, said fibrous mats being composed of woven strands, said filterbags being composed of highly dispersed non-woven fibers ranging from0.1 to 15 microns in diameter, said fan being operative to draw airthrough said bags such that the face velocity of said air through saidbags ranges from 10 to 40 cu. ft./sq. ft./min., the resistance to theflow of said air being such 8 that the pressure drop across the face ofsaid bags is within the range of from .0007 to .007 psi.

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